The aquaculture industry makes a significant contribution to the supply of aquatic food for the global population and is expected to become the main sector for blue food production.
Despite the positive benefits of aquaculture, it can also have considerable negative impacts, including the degradation of aquatic habitats and the introduction of non-native species, among other impacts.
When aquaculture is done well, with proper practices and in appropriate locations, it can generate a variety of environmental benefits. This offers the opportunity to reduce the occurrence or risk of negative impacts from the aquaculture industry and enhance positive impacts.
In this context, the concept of “restorative aquaculture” is based on identifying, recognizing, and increasing the use of practices that can provide restorative outcomes.
A team of researchers from The Nature Conservancy, the World Bank, FAO, Shanghai Jiao Tong University, Oceans 2050 Foundation, among other academic and non-governmental organizations, published a study providing a definition of “restorative aquaculture” and describing six global principles for the implementation of restorative practices.
They also identified a range of information needs, data, and tools to support further exploration of the “restorative aquaculture” approach.
Definition of “Restorative Aquaculture”
The Nature Conservancy (2021) defines “Restorative Aquaculture” as something that occurs when “commercial or subsistence aquaculture provides direct ecological benefits to the environment, with the potential to generate net positive environmental outcomes.”
According to the researchers, promoting the use of a clear description of restorative aquaculture is useful because it can help understand where the intention or objectives of different approaches may necessarily diverge.
Restorative Strategies and Approaches
According to the study, restorative aquaculture practices draw from restorative agricultural systems, characterized by:
Approaches that can be applied to the aquaculture landscape and the surrounding area, such as interventions like natural habitat.
Approaches applied to the aquaculture practice itself.
“When implementing restorative practices, it will be important for the industry, government, and community to recognize that restorative aquaculture is context-specific and not a one-size-fits-all solution,” the researchers emphasize.
Principles for Restorative Aquaculture
The authors of the study report that six global principles for restorative aquaculture have been identified, which can guide the industry and government in understanding how restoration activities can be implemented to generate positive outcomes for the ecosystem.
“These principles are applicable to both new and expanded aquaculture activities, as well as to practices and decision-making in existing farms, which could, for example, introduce or modify gear or management approaches to better create opportunities for environmental benefits,” they highlight.
Principle 1: Locate farms where environmental benefits can be generated
Local environmental characteristics and the health of the surrounding ecosystem will influence the type and scope of benefits that can be generated.
Principle 2: Cultivate species that can provide intended environmental benefits
The species cultivated will significantly influence the type and scope of benefits that can be provided. Different species and species groups have different natural functions and growth rates, which, for example, influence the case of extractive species such as bivalves and seaweeds, in their rates of filtration and nutrient absorption.
Principle 3: Prioritize aquaculture equipment that enhances the delivery of environmental benefits
Certain types of cultivation equipment and support structures can increase foraging, spawning, and refuge habitat for wild fish and other species. Equipment can be selected to reduce the risks of negative effects, such as entanglement or plastic pollution, and improve positive effects for local fauna.
Principle 4: Adopt aquaculture management practices that can enhance local environmental benefits
The timing of construction, seeding, harvest, maintenance practices, and farm configurations can influence the extent to which an operation can generate environmental benefits.
Environmental benefits could be diminished, for example, if the harvest of cultivated biomass occurs at a time that coincides with seasonal use of the area by fish populations.
Principle 5: Strive to farm at an intensity or scale that can enhance ecosystem outcomes
Ideally, restorative aquaculture should occur at a scale and intensity that considers the needs of the local waterbody. While it is not the responsibility of aquaculturists to address, for example, eutrophication effects caused by land runoff, decisions can be made that could increase the returned benefit, such as increasing shellfish biomass (without exceeding storage or carrying capacity) to intentionally enhance water filtration.
Principle 6: Provide data, information, knowledge, and technical capacity to quantify and recognize environmental, social, and economic benefits
Commercial aquaculture can be limited by space or resource overlap and social concern about negative impacts. In addition to ecological benefits, restorative aquaculture should also seek to support social and economic benefits in communities, including livelihood opportunities, education, inclusion, and equity. However, enabling a positive outcome for restorative aquaculture is ultimately a shared responsibility.
To maximize the benefits of restorative practices, communities and governments will also need to recognize, foster, and adequately value social, economic, and environmental benefits in their regulatory capacity.
Promoting the Restorative Approach
The researchers cite that increasing the adoption of restorative aquaculture practices in new aquaculture activities as well as in existing sectors and farms has the potential to generate significant environmental, social, and economic outcomes.
“We need to expand our understanding of how restorative practices can reliably provide environmental benefits,” they said.
“Fostering a social and regulatory environment that rewards the value of restorative practices through non-commercial mechanisms and market mechanisms will empower restorative practice approaches to be economically viable,” they conclude.
Heidi K. Alleway
Provide Food and Water, The Nature Conservancy,
Arlington, VA, USA.
Reference (open access)
Alleway, H. K., Waters, T. J., Brummett, R., Cai, J., Cao, L., Cayten, M. R., Costa-Pierce, B. A., Dong, Y.-W., Brandstrup Hansen, S. C., Liu, S., Liu, Q., Shelley, C., Theuerkauf, S. J., Tucker, L., Wang, Y., & Jones, R. C. (2023). Global principles for restorative aquaculture to foster aquaculture practices that benefit the environment. Conservation Science and Practice, e12982. https://doi.org/10.1111/csp2.12982